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// Output streams -*- C++ -*-

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003

// Free Software Foundation, Inc.

//

// This file is part of the GNU ISO C++ Library.  This library is free

// software; you can redistribute it and/or modify it under the

// terms of the GNU General Public License as published by the

// Free Software Foundation; either version 2, or (at your option)

// any later version.

// This library is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along

// with this library; see the file COPYING.  If not, write to the Free

// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,

// USA.

// As a special exception, you may use this file as part of a free software

// library without restriction.  Specifically, if other files instantiate

// templates or use macros or inline functions from this file, or you compile

// this file and link it with other files to produce an executable, this

// file does not by itself cause the resulting executable to be covered by

// the GNU General Public License.  This exception does not however

// invalidate any other reasons why the executable file might be covered by

// the GNU General Public License.

//

// ISO C++ 14882: 27.6.2  Output streams

//

/** @file ostream

 *  This is a Standard C++ Library header.

 */

#ifndef _GLIBCXX_OSTREAM

#define _GLIBCXX_OSTREAM 1

#pragma GCC system_header

#include <ios>

namespace std

{

  // [27.6.2.1] Template class basic_ostream

  /**

   *  @brief  Controlling output.

   *

   *  This is the base class for all output streams.  It provides text

   *  formatting of all builtin types, and communicates with any class

   *  derived from basic_streambuf to do the actual output.

  */

  template<typename _CharT, typename _Traits>

    class basic_ostream : virtual public basic_ios<_CharT, _Traits>

    {

    public:

      // Types (inherited from basic_ios (27.4.4)):

      typedef _CharT                                    char_type;

      typedef typename _Traits::int_type                int_type;

      typedef typename _Traits::pos_type                pos_type;

      typedef typename _Traits::off_type                off_type;

      typedef _Traits                                   traits_type;

      // Non-standard Types:

      typedef basic_streambuf<_CharT, _Traits>          __streambuf_type;

      typedef basic_ios<_CharT, _Traits>                __ios_type;

      typedef basic_ostream<_CharT, _Traits>            __ostream_type;

      typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> >

                                                        __num_put_type;

      typedef ctype<_CharT>                             __ctype_type;

      template<typename _CharT2, typename _Traits2>

        friend basic_ostream<_CharT2, _Traits2>&

        operator<<(basic_ostream<_CharT2, _Traits2>&, _CharT2);

      template<typename _Traits2>

        friend basic_ostream<char, _Traits2>&

        operator<<(basic_ostream<char, _Traits2>&, char);

      template<typename _CharT2, typename _Traits2>

        friend basic_ostream<_CharT2, _Traits2>&

        operator<<(basic_ostream<_CharT2, _Traits2>&, const _CharT2*);

      template<typename _Traits2>

        friend basic_ostream<char, _Traits2>&

        operator<<(basic_ostream<char, _Traits2>&, const char*);

      template<typename _CharT2, typename _Traits2>

        friend basic_ostream<_CharT2, _Traits2>&

        operator<<(basic_ostream<_CharT2, _Traits2>&, const char*);

      // [27.6.2.2] constructor/destructor

      /**

       *  @brief  Base constructor.

       *

       *  This ctor is almost never called by the user directly, rather from

       *  derived classes' initialization lists, which pass a pointer to

       *  their own stream buffer.

      */

      explicit

      basic_ostream(__streambuf_type* __sb)

      { this->init(__sb); }

      /**

       *  @brief  Base destructor.

       *

       *  This does very little apart from providing a virtual base dtor.

      */

      virtual

      ~basic_ostream() { }

      // [27.6.2.3] prefix/suffix

      class sentry;

      friend class sentry;

      // [27.6.2.5] formatted output

      // [27.6.2.5.3]  basic_ostream::operator<<

      //@{

      /**

       *  @brief  Interface for manipulators.

       *

       *  Manuipulators such as @c std::endl and @c std::hex use these

       *  functions in constructs like "std::cout << std::endl".  For more

       *  information, see the iomanip header.

      */

      inline __ostream_type&

      operator<<(__ostream_type& (*__pf)(__ostream_type&));

      inline __ostream_type&

      operator<<(__ios_type& (*__pf)(__ios_type&));

      inline __ostream_type&

      operator<<(ios_base& (*__pf) (ios_base&));

      //@}

      // [27.6.2.5.2] arithmetic inserters

      /**

       *  @name Arithmetic Inserters

       *

       *  All the @c operator<< functions (aka <em>formatted output

       *  functions</em>) have some common behavior.  Each starts by

       *  constructing a temporary object of type std::basic_ostream::sentry.

       *  This can have several effects, concluding with the setting of a

       *  status flag; see the sentry documentation for more.

       *

       *  If the sentry status is good, the function tries to generate

       *  whatever data is appropriate for the type of the argument.

       *

       *  If an exception is thrown during insertion, ios_base::badbit

       *  will be turned on in the stream's error state without causing an

       *  ios_base::failure to be thrown.  The original exception will then

       *  be rethrown.

      */

      //@{

      /**

       *  @brief  Basic arithmetic inserters

       *  @param  A variable of builtin type.

       *  @return  @c *this if successful

       *

       *  These functions use the stream's current locale (specifically, the

       *  @c num_get facet) to perform numeric formatting.

      */

      __ostream_type&

      operator<<(long __n);

      __ostream_type&

      operator<<(unsigned long __n);

      __ostream_type&

      operator<<(bool __n);

      __ostream_type&

      operator<<(short __n);

      __ostream_type&

      operator<<(unsigned short __n);

      __ostream_type&

      operator<<(int __n);

      __ostream_type&

      operator<<(unsigned int __n);

#ifdef _GLIBCXX_USE_LONG_LONG

      __ostream_type&

      operator<<(long long __n);

      __ostream_type&

      operator<<(unsigned long long __n);

#endif

      __ostream_type&

      operator<<(double __f);

      __ostream_type&

      operator<<(float __f);

      __ostream_type&

      operator<<(long double __f);

      __ostream_type&

      operator<<(const void* __p);

      /**

       *  @brief  Extracting from another streambuf.

       *  @param  sb  A pointer to a streambuf

       *

       *  This function behaves like one of the basic arithmetic extractors,

       *  in that it also constructs a sentry object and has the same error

       *  handling behavior.

       *

       *  If @a sb is NULL, the stream will set failbit in its error state.

       *

       *  Characters are extracted from @a sb and inserted into @c *this

       *  until one of the following occurs:

       *

       *  - the input stream reaches end-of-file,

       *  - insertion into the output sequence fails (in this case, the

       *    character that would have been inserted is not extracted), or

       *  - an exception occurs while getting a character from @a sb, which

       *    sets failbit in the error state

       *

       *  If the function inserts no characters, failbit is set.

      */

      __ostream_type&

      operator<<(__streambuf_type* __sb);

      //@}

      // [27.6.2.6] unformatted output functions

      /**

       *  @name Unformatted Output Functions

       *

       *  All the unformatted output functions have some common behavior.

       *  Each starts by constructing a temporary object of type

       *  std::basic_ostream::sentry.  This has several effects, concluding

       *  with the setting of a status flag; see the sentry documentation

       *  for more.

       *

       *  If the sentry status is good, the function tries to generate

       *  whatever data is appropriate for the type of the argument.

       *

       *  If an exception is thrown during insertion, ios_base::badbit

       *  will be turned on in the stream's error state.  If badbit is on in

       *  the stream's exceptions mask, the exception will be rethrown

       *  without completing its actions.

      */

      //@{

      /**

       *  @brief  Simple insertion.

       *  @param  c  The character to insert.

       *  @return  *this

       *

       *  Tries to insert @a c.

       *

       *  @note  This function is not overloaded on signed char and

       *         unsigned char.

      */

      __ostream_type&

      put(char_type __c);

      // Core write functionality, without sentry.

      void

      _M_write(const char_type* __s, streamsize __n)

      {

        streamsize __put = this->rdbuf()->sputn(__s, __n);

        if (__put != __n)

          this->setstate(ios_base::badbit);

      }

      /**

       *  @brief  Character string insertion.

       *  @param  s  The array to insert.

       *  @param  n  Maximum number of characters to insert.

       *  @return  *this

       *

       *  Characters are copied from @a s and inserted into the stream until

       *  one of the following happens:

       *

       *  - @a n characters are inserted

       *  - inserting into the output sequence fails (in this case, badbit

       *    will be set in the stream's error state)

       *

       *  @note  This function is not overloaded on signed char and

       *         unsigned char.

      */

      __ostream_type&

      write(const char_type* __s, streamsize __n);

      //@}

      /**

       *  @brief  Synchronizing the stream buffer.

       *  @return  *this

       *

       *  If @c rdbuf() is a null pointer, changes nothing.

       *

       *  Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1,

       *  sets badbit.

      */

      __ostream_type&

      flush();

      // [27.6.2.4] seek members

      /**

       *  @brief  Getting the current write position.

       *  @return  A file position object.

       *

       *  If @c fail() is not false, returns @c pos_type(-1) to indicate

       *  failure.  Otherwise returns @c rdbuf()->pubseekoff(0,cur,out).

      */

      pos_type

      tellp();

      /**

       *  @brief  Changing the current write position.

       *  @param  pos  A file position object.

       *  @return  *this

       *

       *  If @c fail() is not true, calls @c rdbuf()->pubseekpos(pos).  If

       *  that function fails, sets failbit.

      */

      __ostream_type&

      seekp(pos_type);

      /**

       *  @brief  Changing the current write position.

       *  @param  off  A file offset object.

       *  @param  dir  The direction in which to seek.

       *  @return  *this

       *

       *  If @c fail() is not true, calls @c rdbuf()->pubseekoff(off,dir).

       *  If that function fails, sets failbit.

      */

       __ostream_type&

      seekp(off_type, ios_base::seekdir);

    protected:

      explicit

      basic_ostream() { }

    };

  /**

   *  @brief  Performs setup work for output streams.

   *

   *  Objects of this class are created before all of the standard

   *  inserters are run.  It is responsible for "exception-safe prefix and

   *  suffix operations."  Additional actions may be added by the

   *  implementation, and we list them in

   *  http://gcc.gnu.org/onlinedocs/libstdc++/17_intro/howto.html#5

   *  under [27.6] notes.

  */

  template <typename _CharT, typename _Traits>

    class basic_ostream<_CharT, _Traits>::sentry

    {

      // Data Members:

      bool                              _M_ok;

      basic_ostream<_CharT,_Traits>&    _M_os;

    public:

      /**

       *  @brief  The constructor performs preparatory work.

       *  @param  os  The output stream to guard.

       *

       *  If the stream state is good (@a os.good() is true), then if the

       *  stream is tied to another output stream, @c is.tie()->flush()

       *  is called to synchronize the output sequences.

       *

       *  If the stream state is still good, then the sentry state becomes

       *  true ("okay").

      */

      explicit

      sentry(basic_ostream<_CharT,_Traits>& __os);

      /**

       *  @brief  Possibly flushes the stream.

       *

       *  If @c ios_base::unitbuf is set in @c os.flags(), and

       *  @c std::uncaught_exception() is true, the sentry destructor calls

       *  @c flush() on the output stream.

      */

      ~sentry()

      {

        // XXX MT

        if (_M_os.flags() & ios_base::unitbuf && !uncaught_exception())

          {

            // Can't call flush directly or else will get into recursive lock.

            if (_M_os.rdbuf() && _M_os.rdbuf()->pubsync() == -1)

              _M_os.setstate(ios_base::badbit);

          }

      }

      /**

       *  @brief  Quick status checking.

       *  @return  The sentry state.

       *

       *  For ease of use, sentries may be converted to booleans.  The

       *  return value is that of the sentry state (true == okay).

      */

      operator bool() const

      { return _M_ok; }

    };

  // [27.6.2.5.4] character insertion templates

  //@{

  /**

   *  @brief  Character inserters

   *  @param  out  An output stream.

   *  @param  c  A character.

   *  @return  out

   *

   *  Behaves like one of the formatted arithmetic inserters described in

   *  std::basic_ostream.  After constructing a sentry object with good

   *  status, this function inserts a single character and any required

   *  padding (as determined by [22.2.2.2.2]).  @c out.width(0) is then

   *  called.

   *

   *  If @a c is of type @c char and the character type of the stream is not

   *  @c char, the character is widened before insertion.

  */

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c);

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)

    { return (__out << __out.widen(__c)); }

  // Specialization

  template <class _Traits>

    basic_ostream<char, _Traits>&

    operator<<(basic_ostream<char, _Traits>& __out, char __c);

  // Signed and unsigned

  template<class _Traits>

    basic_ostream<char, _Traits>&

    operator<<(basic_ostream<char, _Traits>& __out, signed char __c)

    { return (__out << static_cast<char>(__c)); }

  template<class _Traits>

    basic_ostream<char, _Traits>&

    operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)

    { return (__out << static_cast<char>(__c)); }

  //@}

  //@{

  /**

   *  @brief  String inserters

   *  @param  out  An output stream.

   *  @param  s  A character string.

   *  @return  out

   *  @pre  @a s must be a non-NULL pointer

   *

   *  Behaves like one of the formatted arithmetic inserters described in

   *  std::basic_ostream.  After constructing a sentry object with good

   *  status, this function inserts @c traits::length(s) characters starting

   *  at @a s, widened if necessary, followed by any required padding (as

   *  determined by [22.2.2.2.2]).  @c out.width(0) is then called.

  */

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s);

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits> &

    operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s);

  // Partial specializationss

  template<class _Traits>

    basic_ostream<char, _Traits>&

    operator<<(basic_ostream<char, _Traits>& __out, const char* __s);

  // Signed and unsigned

  template<class _Traits>

    basic_ostream<char, _Traits>&

    operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)

    { return (__out << reinterpret_cast<const char*>(__s)); }

  template<class _Traits>

    basic_ostream<char, _Traits> &

    operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)

    { return (__out << reinterpret_cast<const char*>(__s)); }

  //@}

  // [27.6.2.7] standard basic_ostream manipulators

  /**

   *  @brief  Write a newline and flush the stream.

   *

   *  This manipulator is often mistakenly used when a simple newline is

   *  desired, leading to poor buffering performance.  See

   *  http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#2 for more

   *  on this subject.

  */

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    endl(basic_ostream<_CharT, _Traits>& __os)

    { return flush(__os.put(__os.widen('\n'))); }

  /**

   *  @brief  Write a null character into the output sequence.

   *

   *  "Null character" is @c CharT() by definition.  For CharT of @c char,

   *  this correctly writes the ASCII @c NUL character string terminator.

  */

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    ends(basic_ostream<_CharT, _Traits>& __os)

    { return __os.put(_CharT()); }

  /**

   *  @brief  Flushes the output stream.

   *

   *  This manipulator simply calls the stream's @c flush() member function.

  */

  template<typename _CharT, typename _Traits>

    basic_ostream<_CharT, _Traits>&

    flush(basic_ostream<_CharT, _Traits>& __os)

    { return __os.flush(); }

} // namespace std

#ifndef _GLIBCXX_EXPORT_TEMPLATE

# include <bits/ostream.tcc>

#endif

#endif  /* _GLIBCXX_OSTREAM */